Apparatus, systems, and methods for battery life based wireless communication scheduling

ABSTRACT

Systems and methods compare a first battery life value associated with a first wireless device with a second battery life value associated with a second wireless device. Based on the comparison, systems and methods adjust a communication schedule by allocating timeslots of the communication schedule to the first wireless device and transmit the adjusted communication schedule to the first wireless device.

TECHNICAL FIELD

The subject matter relates to the field of wireless communications. Morespecifically, but not by way of limitation, the subject matter disclosestechniques for battery life based wireless communication scheduling.

BACKGROUND

Communication systems transfer data in accordance with one or morewireless communication protocols. For example, a communication systemmay utilize a wireless local area network (WLAN) communication protocol(e.g., Wi-Fi based on IEEE 802.11 standards), Bluetooth/Bluetooth LowEnergy (BT) communication protocols (e.g., based on BT SIG standards),and/or Zigbee (ZB) communication protocol (e.g., based on IEEE 802.15.4standards). Some communication protocols provide a mechanism for acommunication system to wake up for predetermined periods to communicateand sleep during other periods. For example, operating according to thetarget wake time (TWT) mechanism of the 802.11 standards (e.g.,802.11ax), an access point (AP) can schedule wake intervals during whichone or more stations (STAs) in a basic service set (BSS) can operate inan awake state during a TWT session to communicate and operate in asleep state for the remainder of the wake interval. Many suchcommunication systems are battery-powered wireless devices having a needto minimize unnecessary power consumption.

BRIEF DESCRIPTION OF THE DRAWINGS

Some embodiments are illustrated by way of example and not limitation inthe figures of the accompanying drawings in which:

FIG. 1 is a network diagram illustrating a communication network, inaccordance with embodiments;

FIG. 2A is a timing diagram illustrating a TWT schedule, in accordancewith embodiments;

FIG. 2B is an information element diagram illustrating a TWT element, inaccordance with embodiments;

FIG. 3 is a block diagram illustrating a communication device, inaccordance with embodiments;

FIG. 4 is a block diagram illustrating another communication device, inaccordance with embodiments;

FIG. 5 is an interactive flow diagram illustrating a method ofscheduling communication based on battery life, in accordance withembodiments;

FIG. 6 is a flow diagram illustrating a method of TWT scheduling basedon battery life of a STA, in accordance with embodiments;

FIG. 7 illustrates an adjustment to a TWT schedule, based on batterylife of a STA, in accordance with an embodiment;

FIG. 8 is flow diagram illustrating another method of TWT schedulingbased on battery life of a STA, in accordance with embodiments;

FIGS. 9 and 10 illustrate other adjustments to a TWT schedule based onbattery life of a STA, in accordance with embodiments; and

FIG. 11 is a block diagram illustrating an electronic device, inaccordance with embodiments.

DETAILED DESCRIPTION

Apparatus, systems and methods for battery life based wirelesscommunication scheduling are described. In the following description,for purposes of explanation, numerous examples and embodiments are setforth in order to provide a thorough understanding of the claimedsubject matter. It will be evident to one skilled in the art that theclaimed subject matter may be practiced in other embodiments. Someembodiments are now briefly introduced and then discussed in more detailalong with other embodiments beginning with FIG. 1.

In networks where wireless devices periodically wake for communication(e.g., according to the 802.11ax TWT mechanism), a central networkdevice (e.g., an AP) may schedule (e.g., using time divisionmultiplexing (TDM)) the wake and sleep timing among the wirelessdevices. Such central network devices do not conventionally use powerstatus information (e.g., battery life) of any of the wireless devicesto define (e.g. or reschedule) wake and sleep timing for communicationschedules.

Embodiments described herein provide techniques to dynamically schedule(e.g. or reschedule) wake and sleep timing associated with communicationby considering the remaining battery life of a wireless device. The termbattery life includes an estimated operation time the battery operatedwireless device can run based on its current power consumption rate. Forexample, battery life may be expressed as a numerical value representingthe remaining operation time, where the battery life is calculated basedon remaining battery charge (e.g., battery capacity) and instantaneouspower consumption rate.

A system of one or more computers can be configured to performparticular operations or actions by virtue of having software, firmware,hardware, or a combination of them installed on the system that inoperation causes or cause the system to perform the actions. One or morecomputer programs can be configured to perform particular operations oractions by virtue of including instructions that when executed by dataprocessing apparatus, cause the apparatus to perform the actions.

General aspects include a first communication device determining currentor predicted power status associated with the first communication deviceand transmitting its power status to a second communication device. Thesecond communication device evaluates the power status information andgenerates a communication schedule (e.g., or an adjusted communicationschedule) based on the evaluation, then transmits the communicationschedule to the first communication device. The first communicationdevice then manages its own power consumption based on the communicationschedule received from the second communication device.

One aspect includes an AP receiving a first TWT element from a firstwireless device. The method also includes responsive to the first TWTelement, comparing a first battery life value associated with the firstwireless device with a second battery life value associated with asecond wireless device. The method also includes based on thecomparison, adjusting a communication schedule by allocating timeslotsof a TWT session to the first wireless device. The method also includestransmitting a second TWT element to the first wireless device, thesecond TWT element defining the TWT session. Other embodiments of thisaspect include corresponding computer systems, apparatus, and computerprograms recorded on one or more computer storage devices, eachconfigured to perform the actions of the methods.

One aspect includes a communication device with communication protocollogic configured to receive a first TWT element and a first battery lifevalue from a first wireless device. The device also includes a memorysystem configured to store a plurality of battery life values. Thedevice also includes a power status evaluator configured to access thememory system to compare the first battery life value with a secondbattery life value associated with a second wireless device. The devicealso includes a scheduler, responsive to the first battery life valuebeing less than the second battery life value, configured to associatethe first wireless device with a TWT session, where the communicationprotocol logic is configured to transfer to the first wireless device asecond TWT element defining the TWT session.

One aspect includes a communication device including a transceiver. Thedevice also includes communication protocol logic configured to use thetransceiver to: transmit a battery life value to an AP, receive, fromthe AP, an incoming TWT element that is based at least in part on thebattery life value, and communicate data with the AP during a TWTsession of a TWT wake interval defined by the incoming TWT element,where the communication device is configured to operate in a first modeduring the communication of the data and operate in a second mode afterthe communication of the data and during the TWT wake interval, wherethe operation in the second mode consumes less battery power than theoperation in the first mode.

One aspect includes a system including one or more antennas configuredto transmit and receive radio frequency signals. The system alsoincludes an integrated circuit (IC) coupled to the antenna, the IC mayinclude: a transceiver; and communication protocol logic configured touse the transceiver to: transmit an outgoing TWT element and a batterylife value to an AP, receive, from the AP, an incoming TWT element thatis based at least in part on the battery life value. The system alsocommunicates data with the AP during a TWT session of a TWT wakeinterval defined by the incoming TWT element, where the IC is configuredto operate in a first mode during the communication of the data andoperate in a second mode after the communication of the data and duringthe TWT wake interval, where the operation in the second mode consumesless battery power than the operation in the first mode.

In this way, embodiments can utilize a wireless device's current batterylife to schedule wireless device wake and sleep timing such that thedepletion rate of the wireless device's battery life is slowed andconsequently, operation time for the entire network can be extended.Although some embodiments are described with respect to WLANcommunication protocol, other embodiments may be based on othercommunication protocols such as ZB or BT communication protocols,without departing from the inventive subject matter.

The detailed description below includes references to the accompanyingdrawings, which form a part of the detailed description. The drawingsshow illustrations in accordance with embodiments. These embodiments,which are also referred to herein as “examples,” are described in enoughdetail to enable those skilled in the art to practice embodiments of theclaimed subject matter. The embodiments may be combined, otherembodiments may be utilized, or structural, logical, and electricalchanges may be made without departing from the scope of what is claimed.The following detailed description is, therefore, not to be taken in alimiting sense, and the scope is defined by the appended claims andtheir equivalents.

FIG. 1 is a network diagram illustrating a communication network 100, inaccordance with embodiments. Embodiments of the communication network100 are described with respect to a WLAN but the communication network100 may utilize other wireless communication protocols without departingfrom the claimed subject matter. Example network communication devicesare shown to include an AP 102 (e.g., or a STA implementing a softwareAP), STA 1 104 (e.g., laptop computer), STA 2 106 (e.g., mobile phone),STA 3 108 (e.g., wireless camera), STA 4 112 (e.g., tablet), STA 5 110(e.g., temperature sensor), and STA 6 114 (e.g., wireless camera).

In embodiments, the AP 102 may schedule periods for one or more of theSTAs 1-6 to communicate via the wireless medium. During periods that aSTA is scheduled to communicate, the STA may power its communicationcircuitry to enable communication. During periods that the STA isscheduled not to communicate, the STA need not consume power to operateits communication circuitry, thus saving power. In embodiments, when thecommunication network 100 is compatible with 802.11ax, the AP 102 mayutilize TDM to schedule TWT sessions associated with one or more of theSTAs 1-6. The AP and a STA may agree on wake periods for the STA totransmit and/or receive data packets and doze periods during which theSTA can conserve energy (e.g., battery power). An example TWT mechanismis described in more detail with respect to FIG. 2. AP scheduling of TWTsessions not only conserves energy it can also reduce contention amongSTAs and support collision free and deterministic operation that meetsquality of service targets.

In embodiments, a battery capacity of each battery operated STA 1-6represents a measure of charge stored by the STAs battery. Of course,battery capacities and power consumption rates may vary among STAsdepending on device specifications and the functional demands of theSTA. As used herein, battery life represents an amount of time a STA cancontinue to operate given its current battery capacity and powerconsumption rate. For example, the STA 6 114 may have a relatively shortbattery life when its battery capacity is relatively low and its powerconsumption rate is relatively high (e.g., to support image processingand frequent wireless transmissions). On the other hand, STA 5 110 mayhave a relatively long battery life when its battery capacity isrelatively high and its power consumption rate is relatively low (e.g.,to support occasional temperature sensing and infrequent wirelesstransmissions).

Conventional APs do not consider battery life of STAs in schedulingperiods for STAs to communicate via the wireless medium. The inventorshave discovered scheduling techniques that utilize STA's battery lifeinformation to extend (e.g., compared to conventional scheduling) theoverall time that STAs in the communication network have sufficientbattery power to remain operational. Compared to conventional schedulingtechniques, embodiments described herein can identify STAs withrelatively low battery life and reschedule communication periods to slowpower consumption and extend the STAs' remaining battery life. Invarious embodiments, this is achieved through STAs reporting theirbattery life and the AP prioritizing TWT session allocation to STAs withthe lowest battery life.

FIG. 2A is a timing diagram illustrating a target wake time (TWT)schedule, in accordance with embodiments. FIG. 2B is an informationelement diagram illustrating a TWT element 250 used by the AP 202 andthe STA 204 to negotiate 206, teardown 214, otherwise participate in TWTagreements, in accordance with embodiments. The control field 256 of theTWT element 250 can be used to indicate whether the AP 202 and the STA204 are negotiating for operation according to individual TWT orbroadcast TWT as defined in 802.11ax. Referring to FIGS. 2A and 2B, TWT207 represents the start time of the first TWT session 208 and the TWT207 may be indicated in the TWT field 260 of the TWT element 250. TWTsessions 208, having a duration 210 defined in the minimum TWT wakeduration field 264, are periods in which the STA 204 operates in anawake state to communicate data with the AP 202. The wake interval 212,defined in the TWT wake interval field 266, is the time interval betweenthe start of adjacent TWT sessions 208. In embodiments, the STA 204 canoperate in a sleep or doze state between TWT sessions 208 to conserveenergy.

In some embodiments, the AP 202 may support assigning multiple STAs to aTWT session 208 (e.g., a group TWT session) rather than one STA per TWTsession 208. In such case, each STA assigned to the TWT session 208 isprovided with a group identifier encoded in the TWT group assignmentfield 262. For example, the STAs in the group may wake up at the startof the TWT session 208 and communicate at non-overlapping times duringthe TWT session 208. In embodiments, a group STA (e.g., each STA in agroup) may communicate responsive to a trigger indicator in the requesttype field 258 of the TWT element 250. Once a group STA has finishedcommunicating, it may enter into a doze mode for the remainder of theTWT session 208.

Although FIG. 2A shows a TWT session 208 that occurs two times in thefixed period of time T, the TWT session 208 may occur any number oftimes (e.g., as defined by the wake interval 212) during the fixedperiod T (e.g., from time zero to time T). In addition, as shown inFIGS. 6, 8, and 9, an AP may schedule other TWT sessions (not shown)during times (e.g., timeslots) that are not occupied by the TWT session208.

Conventional APs do not consider STAs battery life when scheduling theirparticipation in TWT sessions. For example, when no timeslots areavailable to schedule a new TWT session for a STA with short batterylife, this STA may need to stay awake and contend for medium accessusing carrier sense multiple access with collision avoidance (CSMA/CA).Also, if a STA with short battery life is the last to be triggered in agroup TWT session, it may consume more power than necessary as it waitsin an awake mode to be triggered to communicate. As a result,conventional techniques may not allow a STA with short battery life tobenefit from potential power saving benefits of the TWT mechanism.Communication devices that use battery life for wireless communicationscheduling are shown and described with respect to FIGS. 3 and 4.

FIG. 3 is a block diagram illustrating a communication device 300, inaccordance with embodiments. The communication device 300 may bedisposed on a substrate 301 such as a printed circuit board (PCB). Thebus system 303 may include inter-chip busses, intra-chip busses,coexistence busses, or any other communication line to connect thecircuits and/or logic blocks, which may be disposed on an IC chip ordiscrete IC chips.

The communication device 300 is shown to include transceiver 308,scheduler 310, communication protocol logic 311, antenna selector 316,power status evaluator 318, processing devices 320, and memory system322, which are each discussed in more detail below. In embodiments, thecommunication device 300 may provide the functionality of the AP 102 ofFIG. 1.

In embodiments, the processing devices 320 are used to implementcommunication device 300 operations utilizing instructions 324 (e.g.,firmware or microcode) and/or data structures organized within thememory system 322. Although shown as single blocks, processing devices320 and memory systems 322 may include multiple shared or dedicatedresources distributed among the various blocks (e.g., 308, 310, 311,316, 318) of the communication device 300. Example processing devicesand memory systems are described in more detail with respect to FIG. 11.

Communication device 300 may include or be coupled to antennas 304 and306 through antenna selector 316, which may include any selection logic(e.g., hardware, software, or combination) known in the art. When theantenna selector 316 selects an antenna, it couples the antenna to thetransceiver 308 for RF signal reception and transmission. Inembodiments, each antenna 304 and 306 can represent one or moreantennas. For example, in some embodiments, the antenna selector 316(e.g., operating as switch circuitry) may couple the communicationdevice 300 to one or more antenna arrays (e.g., a phased array) and/orantenna clusters including any number of antennae (e.g., six or eight)exclusively paired with or shared among communication protocol logic311.

The transceiver 308 facilitates transmitting and receiving of RF signalsaccording to one or more communication protocols. In embodiments, whenoperating as a receiver, the transceiver 308 processes received RFsignals in the analog domain, digitizes them, and demodulatescorresponding digital data to provide a decoded sequence of 1s and 0s tothe communication protocol logic 311 for further processing (e.g.,packet processing). When operating as a transmitter, the transceiver 308generally performs the operations in reverse, receiving a sequence of 1sand 0s from the communication protocol logic 311, modulating the signal,and outputting an analog signal for transmission by one or more of theantennas 304 and 306.

The communication protocol logic 311 includes the instructions andhardware to support communication protocols defined by one or morecommunication protocol standards (e.g., according to WLAN, BT, BLEand/or ZB communication protocols). The PHY logic 312 may includededicated circuitry and/or processor executed instructions to implementall or portions of electrical and physical specifications of acommunication protocol and defines the relationship between thecommunication device 300 and the transmission medium (e.g., all orportions of the physical layer of the OSI reference model). For example,the PHY logic 312 may establish and terminate connections, providecontention resolution and flow control, and provide modulation,demodulation, and/or conversion between digital data and correspondingwirelessly communicated signals. The MAC logic 314 may include dedicatedcircuitry and/or processor executed instructions (e.g., control logic)to implement all or portions of the functional and procedural means totransfer data between network entities (e.g., all or portions of thedata link layer of the OSI reference model). In embodiments, the MAClogic 314 is compatible with 802.11ax and is configured to process TWTelements (e.g., inbound and outbound) associated with STAs for thepurpose of implementing TWT setup/teardown, TWT scheduling, TWTtriggering, and other TWT mechanisms. In embodiments, inbound andoutbound TWT elements may be encoded in any 802.11 frame type. Forexample, an inbound TWT element from a STA may be included in amanagement frame along with an information element indicating batterylife information associated with the STA. The MAC logic 314 may extractand then store the TWT information and battery life information in thememory system 322 to make it available to the scheduler 310 and thepower status evaluator 318, respectively. In embodiments, the MAC logic314 may include or otherwise utilize the scheduler 310 and/or the powerstatus evaluator 318 to schedule TWT sessions for a STA (e.g., thecommunication device 400).

The communication protocol logic 311 may include baseband logic 315 withdedicated circuitry and/or processor executed instructions to managephysical channels and links and other services like error correction,data whitening, hop selection and security according to BT communicationprotocol standards. The baseband logic 315 may include a link controllerthat works with a BT link manager (not shown) in upper BT protocollayers to carry out link level routines like link connection and powercontrol. The baseband logic 315 may also manage asynchronous andsynchronous links, handle packets and do paging and inquiry to accessand inquire BT devices in the area. In embodiments, similar to the MAClogic 314, the baseband logic 315 may populate and/or inspect packetfields for wake/sleep schedule information and/or battery lifeinformation for use by the scheduler 310 and/or the power statusevaluator 318.

In embodiments, collaborative coexistence hardware mechanisms andalgorithms enable communication subsystems to operate concurrentlyand/or simultaneously. For example, the communication device 300 may beincluded on a system on a chip that includes BT communication resourcesand/or ZB communication resources coupled via coexistence interface(s)to WLAN communication resources. In an embodiment, collaborativecoexistence between WLAN, BT, and/or ZB subsystems may be implemented byPacket Traffic Arbitration (PTA) logic (not shown) to pursue optimumperformance for the particular circumstances and design constraints of amulti-network communication system. Through PTA embodiments, targetedquality levels for simultaneous voice, video, and data transmission onan embedded system can be achieved.

The power status evaluator 318 is to evaluate the battery life of othercommunication devices (e.g., the communication device 400) for use bythe scheduler 310 in determining communication schedules. Inembodiments, evaluating battery life includes tracking and comparing thebattery lives of communication devices associated with TWT sessions.

For example, the communication device 300 may receive (e.g., in framesincluding a TWT element) the battery life values for each communicationdevice associated with an existing TWT session and store them in thebattery tables 326. Alternatively or additionally, the power statusevaluator 318 may first estimate a battery life value based on batteryinformation of the communication device (e.g., battery capacity,operation time, and power consumption rate). In embodiments, the powerstatus evaluator 318 may use counting logic and the battery tables 326to track the remaining battery life of each communication device. When anew TWT request is received from a STA, the power status evaluator 318may access the battery tables 326 to compare the battery life value ofthe requesting STA with the battery life values of the STAs associatedwith existing TWT sessions. For example, the power status evaluator 318may indicate in the battery tables 326 a ranking of battery life valuesfrom highest to lowest.

The scheduler 310 is to use the battery life values of communicationdevices to schedule and/or reschedule the timing for communication amongcommunication devices. For example, the scheduler 310 may access thebattery tables 326 (e.g., rankings) and schedule or reschedule TWTsessions based on the battery life values. The scheduler 310 may utilizethe schedule tables 336 to store current and adjusted communicationschedules. Although shown as separate functional blocks, the powerstatus evaluator 318 and/or the scheduler 310 may be implemented bymicrocode or firmware, for example, as part of the MAC logic 314. Inembodiments, power status evaluator 318 and/or scheduler 310 operationsare triggered by TWT elements received from a STA.

FIG. 4 is a block diagram illustrating a communication device 400, inaccordance with embodiments. The communication device 400 may bedisposed on a substrate 401 such as PCB. The bus system 403, transceiver408, communication protocol logic 411, antenna selector 416, antennas404 and 406, processing devices 420, and the memory system 422 may bethe same or similar to those of the communication device 300 of FIG. 3.In embodiments, the communication device 400 may provide thefunctionality of a STA in FIG. 1.

The power status monitor 418 is to track and report power status such asbattery information associated with the communication device 400. Thepower status monitor 418 may receive battery information from anoff-chip (e.g., or on-chip) power management unit (PMU) that managescharging/discharging of the battery 441. For example, power statusmonitor 418 may receive battery life measurements from a host CPU (notshown) that manages device charging functions via PMU 440 andcorresponding circuits. Battery information may include, withoutlimitation, battery life, battery capacity, power consumption rate,battery age, charge and discharge rates, and/or other batteryattributes. In embodiments, the power status monitor 418 calculates thebattery life of the communication device 400 using one or more of thebattery attributes. The battery life may be expressed as a numericalvalue representing the remaining operation time, where the battery lifeis calculated based on remaining battery charge (e.g., battery capacity)and instantaneous power consumption rate. The power status monitor 418may provide battery attributes to the communication protocol logic 411to be transmitted to the communication device 300 for use incommunication scheduling. For example, the MAC logic 414 may include thebattery life value in an information element via a frame that alsoincludes a TWT element (e.g., indicating a TWT request or a TWTteardown). The communication device 400 may transmit battery life valuesperiodically and/or responsive to battery life values meeting orexceeding (e.g., a minimum) battery life threshold 426 stored in thememory system 422.

In the alternative or in addition to the functionality of thecommunication protocol logic 311 of FIG. 3, the communication protocollogic 411 of FIG. 4 is to operate according to a communication schedulethat is based on the battery life of the communication device 400. Inembodiments, the communication schedule is received from thecommunication device 300 and stored in the communication schedule 428.In embodiments, the MAC logic 414 is compatible with 802.11ax and isconfigured to process (e.g., inbound and outbound) TWT elements for thepurpose of implementing TWT setup/teardown, TWT triggering, and otherTWT mechanisms. Inbound and outbound TWT elements may be encoded in any802.11 frame type. For outbound TWT elements, the MAC logic 414 mayframe the TWT element together with a battery life value provided by thepower status monitor 418. For inbound TWT elements, the MAC logic 414may extract then store TWT scheduling parameters in communicationschedule 428 of the memory system 422.

Power manager 410 controls power consumption by the communication device400 based on the communication schedule 428 stored in the memory system422. For example, when the time period has arrived, according to thecommunication schedule, for the communication device 400 to communicatedata, the power manager 410 may cause the transceiver 408, thecommunication protocol logic 411, and/or other communication circuitryto receive sufficient power to wirelessly communicate. Outside of thetime period scheduled for communication, the power manager 410 may causepower to be reduced or removed from the transceiver 408, thecommunication protocol logic 411, and/or other communication circuitry.The power manager 410 may also track power consumption by thecommunication device 400 over time and report it to the power statusmonitor 418. The power manager 410 may include hardware and/or softwarelogic to physically and/or logically control power delivery to variouscomponents and circuitry of the communication device. An exampleinteraction between communication devices for power status basedcommunication scheduling is described with respect to FIG. 5. Examplebattery life based TWT scheduling by an AP is then described withrespect to FIGS. 6-9.

FIG. 5 is an interactive flow diagram illustrating a method 500 ofscheduling communication based on battery life, in accordance withembodiments. The method 500 can be performed by processing logiccomprising hardware (circuitry, dedicated logic, etc.), software (suchas is run on a general-purpose computing system or a dedicated machine),firmware (embedded software), or any combination thereof. In variousembodiments, the method 500 may be performed as shown and described withrespect to the communication device 300 of FIG. 3 and the communicationdevice 400 of FIG. 4

At block 502, the power status monitor 418 monitors a power status ofthe communication device 400. The power status may relate to any sourceof power to the communication device without departing from theinventive subject matter. In embodiments the power status includesbattery information associated with the battery 441, which batteryinformation may be provided by external battery management logic (e.g.,PMU 440). At block 504, the communication device 400 transmits a currentor predicted power status to the communication device 300. The powerstatus monitor 418 may provide raw power status data or power statusdata that has been modified to predict a current or future power statusbased on power capacity, discharge rates, charge rates, consumptionrates, and the like.

At block 506, the power status evaluator 318 of the communication device300 evaluates the received power status. Evaluation may includeorganizing the communication device 400 and other communication devicesbased on differences or similarities in their power status, current orpredicted power consumption rates, throughput requirements, and/or othercommunication device attributes or network attributes (e.g., availablebandwidth, channel congestion, etc.). At block 508, the scheduler 310allocates or reallocates a communication schedule based on theevaluation. For example, when the results of the evaluation indicatesit, a communication schedule may be generated or adjusted to prioritizecommunication by the communication device 400 over other communicationdevices. At block 510, the communication device 300 transmits thecommunication schedule to the communication device 400.

At block 512, the power manager 410 manages power consumption of thecommunication device 400, based on the communication schedule. Batterylife based prioritization of the communication device 400 in thecommunication schedule can reduce the amount of time the communicationdevice 400 must remain awake for communication so that it can sleep toavoid unnecessarily consuming power. Embodiments described in thecontext of TWT scheduling are described in more detail with respect toFIGS. 6-10.

FIG. 6 is a flow diagram illustrating a method 600 of TWT scheduling,based on battery life of a STA, in accordance with embodiments. Themethod 600 can be performed by processing logic comprising hardware(circuitry, dedicated logic, etc.), software (such as is run on ageneral-purpose computing system or a dedicated machine), firmware(embedded software), or any combination thereof. FIG. 7 illustrates anadjustment to TWT scheduling based on battery life of a STA, inaccordance with an embodiment. Existing schedule 702 and adjustedschedule 704 each represent a time-based schedule of TWT sessions, wherethe AP allows one STA per TWT session. In various embodiments, themethod 600 may be performed as shown and described with respect to FIGS.1-5 and 7.

At block 602, the AP 102 receives a request (e.g., a TWT element 250)from STA 6 114 for a new TWT session. Referring to FIG. 7, it can beseen that STA 6 114 is not associated with an existing TWT session inthe existing schedule 702. In the case that the STA 6 114 is alreadyassociated with an existing TWT session and the STA 6 114 senses thatits battery life is low (e.g., less than a battery threshold value), itcan initiate TWT teardown message in a frame together with aninformation element including its battery life value to report how longthe STA 6 114 can operate based on current battery capacity and powerconsumption rate. When the teardown process is successfully completed,the STA 6 114 may then send the new TWT request to the AP 102, forexample requesting a longer TWT wake interval for better powerconservation. When the STA 6 114 requests the new TWT session, it maysend the TWT request to the AP 102 in a frame together with aninformation element reporting its current battery life value.

At block 604, the AP 102 determines that timeslots are not available inthe existing schedule 702 for the requested TWT session. Referring toFIG. 7, open timeslots are represented by the spaces between existingTWT sessions and the scheduler 310 can determine that the TWT session(e.g., see width of new TWT session 705) requested by the STA will notfit into the existing schedule 702.

At block 606, the AP 102 identifies that STA 5 110, associated with theexisting TWT session 703, has a longer battery life than the STA 6 114.For example, the power status evaluator 318 may access the battery table326 in the memory system 322 to compare battery values associated withthe STAs in the existing schedule 702. For example, the battery tables326 may include a ranking of the battery life values from highest tolowest.

The scheduler 310 may determine that the removal of existing TWT session703 from the existing schedule 702 associated with STA 5 110 will freeup timeslots for the TWT session requirements of the STA 6 114. Based onthis determination, at block 608, the AP 102 tears down the existing TWTsession 703 and creates a new TWT session 705 at block 610. At block612, the scheduler 310 of the AP 102 allocates the new TWT session 705to the STA 6 114.

Thus, in the scenario just described, where an AP allows one STA in eachTWT session, the AP can run a rescheduling algorithm for the new TWTrequest. To reschedule, the AP reviews the existing TWT schedulingallocations as well as the remaining battery life of each STA. Ifadditional channel timeslot resources are available, a new TWT sessionis created to accommodate the new TWT request. If sufficient timeslotsare not available, then the AP identifies a STA with a longer batterylife, tears down the corresponding TWT session, and allocates thechannel timeslots to the new TWT request. After the corresponding TWTsession is torn down, the STA with the longer battery life can stillcommunicate with the AP through contention based enhanced distributedchannel access (EDCA) protocol, until it can switch back tocommunication through TWT session again (e.g., as warranted by systemload and battery life changes).

FIG. 8 is flow diagram illustrating another method 800 of TWT schedulingbased on battery life of a STA, in accordance with embodiments. The flowcan be performed by processing logic comprising hardware (circuitry,dedicated logic, etc.), software (such as is run on a general-purposecomputing system or a dedicated machine), firmware (embedded software),or any combination thereof. FIGS. 9 and 10 illustrate adjustments to TWTscheduling based on battery life of a STA, in accordance withembodiments. Existing schedules 902, 1002 and adjusted schedules 904,1004 each represents a time-based schedule of TWT sessions, where the AP102 can associate multiple STAs with a TWT session (e.g., group TWTsessions). In various embodiments, the method 800 may be performed asshown and described with respect to FIGS. 1-5, 9 and 10.

At block 802, the AP 102 receives a TWT request (e.g., a TWT element250) from the STA 6 114 for a TWT session. At block 804, the scheduler310 of the AP 102 determines whether timeslots of an existing TWTsession are available to accommodate the TWT request from the STA 6 114.For example, referring to FIG. 9, the scheduler 310 can review theexisting schedule 902 and determine whether the requested TWT sessioncan fit into the open timeslots within TWT group 2 903.

If sufficient timeslots are available, the method proceeds to block 806where, referring to the adjusted schedule 904 of FIG. 9, the AP 102allocates timeslots of the existing TWT session (e.g., TWT group 2′ 905)to the STA 6 114. In addition, at block 808, the scheduler 310 of the AP102 may prioritize communication within the existing TWT session (e.g.,TWT group 2′ 905) by STA with the lowest battery life. For example, TWTgroup 2′ 905 illustrates STA 6 114 communicating first followed by STA 4112 and STA 3 108, in order of increasing battery life. In embodiments,the AP 102 may use a TWT element to trigger the STA 6 114 to communicatebefore the STA 4 112 and the STA 3 108 during the TWT session.

If the scheduler 310 determines that sufficient timeslots of an existingTWT session are not available to accommodate the TWT request from theSTA 6 114, the method proceeds to block 810 where, referring to theexisting schedule 1002 of FIG. 10, the AP 102 identifies that the STA 5110 associated with an existing TWT session (e.g., TWT group 3 1003) hasa longer battery life than the STA 6 114. Then, at block 812, referringto the adjusted schedule 1004 of FIG. 10, the scheduler 310 removes ordisassociates the STA 5 110 from the existing TWT session (e.g., TWTgroup 3 1003) and at block 814 allocates the freed up timeslots of theexisting TWT session (e.g., TWT group 3′ 1005) to the STA 6 114. Atblock 816, the AP 102 prioritizes communication within the existing TWTsession by STA with the lowest battery life (e.g. using one or more TWTelement triggers).

As discussed, if the AP 102 allows multiple STAs to share a single TWTsession, the AP can prioritize STAs with the shorter battery life sothat these STAs can switch back to low power state for better powerpreservation. In this scenario, when the AP receives a new TWT requestwith a battery life information element, the AP first reviews allexisting TWT sessions and tries to allocate an existing TWT session tothe requesting STA. If the AP cannot find an existing TWT session tosatisfy this requirement, the AP may create a new TWT session if channeltimeslot resource allows to do so, or if not, then the AP can remove oneor more STAs having the longest battery life out of existing TWTsession. By doing that, STAs with the shorter estimated battery life canget more frequent power saving access through TWT scheduling. If a STAdoes not get chance to be scheduled through TWT, it still cancommunicate with AP through contention based protocol (e.g., EDCA).

Thus, embodiments utilize power status information to generatecommunication schedules that facilitate wireless device wake and sleeptiming such that the depletion rate of the wireless device's batterylife is slowed and consequently, operation time for the entire networkcan be extended.

FIG. 11 is a block diagram illustrating an electronic device 1100, inaccordance with embodiments. The electronic device 1100 may fully orpartially include and/or operate the example embodiments of thecommunication device 300 (e.g., an AP), the communication device 400(e.g., a STA), or portions thereof, as described with respect to FIGS.1-10. The electronic device 1100 may be in the form of a computer systemwithin which sets of instructions may be executed to cause theelectronic device 1100 to perform any one or more of the methodologiesdiscussed herein. The electronic device 1100 may operate as a standalonedevice or may be connected (e.g., networked) to other machines. In anetworked deployment, the electronic device 1100 may operate in thecapacity of a server or a client machine in server-client networkenvironment, or as a peer machine in a P2P (or distributed) networkenvironment.

The electronic device 1100 may be an Internet of Things (IoT) device, aserver computer, a client computer, a personal computer (PC), a tablet,a set-top box (STB), a voice controlled hub (VCH), a Personal DigitalAssistant (PDA), a mobile telephone, a web appliance, a network router,switch or bridge, a television, a speaker, a remote control, a monitor,a handheld multi-media device, a handheld video player, a handheldgaming device, or a control panel, or any other machine capable ofexecuting a set of instructions (sequential or otherwise) that specifyactions to be taken by that machine. Further, while only a singleelectronic device 1100 is illustrated, the term “device” shall also betaken to include any collection of machines that individually or jointlyexecute a set (or multiple sets) of instructions to perform any one ormore of the methodologies discussed herein.

The electronic device 1100 is shown to include processor(s) 1102. Inembodiments, the electronic device 1100 and/or processors(s) 1102 mayinclude processing device(s) 1105 such as a System on a Chip processingdevice, developed by Cypress Semiconductor Corporation, San Jose, Calif.Alternatively, the electronic device 1100 may include one or more otherprocessing devices known by those of ordinary skill in the art, such asa microprocessor or central processing unit, an application processor, ahost controller, a controller, a special-purpose processor, a digitalsignal processor (DSP), an application specific integrated circuit(ASIC), a field programmable gate array (FPGA), or the like. Bus system1101 may include a communication block (not shown) to communicate withan internal or external component, such as an embedded controller or anapplication processor, via communication interfaces(s) 1109 and/or bussystem 1101.

Components of the electronic device 1100 may reside on a common carriersubstrate such as, for example, an IC die substrate, a multi-chip modulesubstrate, or the like. Alternatively, components of the electronicdevice 1100 may be one or more separate ICs and/or discrete components.

The memory system 1104 may include volatile memory and/or non-volatilememory which may communicate with one another via the bus system 1101.The memory system 1104 may include, for example, random access memory(RAM) and program flash. RAM may be static RAM (SRAM), and program flashmay be a non-volatile storage, which may be used to store firmware(e.g., control algorithms executable by processor(s) 1102 to implementoperations described herein). The memory system 1104 may includeinstructions 1103 that when executed perform the methods describedherein. Portions of the memory system 1104 may be dynamically allocatedto provide caching, buffering, and/or other memory basedfunctionalities.

The memory system 1104 may include a drive unit providing amachine-readable medium on which may be stored one or more sets ofinstructions 1103 (e.g., software) embodying any one or more of themethodologies or functions described herein. The instructions 1103 mayalso reside, completely or at least partially, within the other memorydevices of the memory system 1104 and/or within the processor(s) 1102during execution thereof by the electronic device 1100, which in someembodiments, constitutes machine-readable media. The instructions 1103may further be transmitted or received over a network via thecommunication interfaces(s) 1109.

While a machine-readable medium is in some embodiments a single medium,the term “machine-readable medium” should be taken to include a singlemedium or multiple media (e.g., a centralized or distributed database,and/or associated caches and servers) that store one or more sets ofinstructions. The term “machine-readable medium” shall also be taken toinclude any medium that is capable of storing or encoding a set ofinstructions for execution by the machine and that cause the machine toperform any one or more of the example operations described herein. Theterm “machine-readable medium” shall accordingly be taken to include,but not be limited to, solid-state memories, and optical and magneticmedia.

The electronic device 1100 is further shown to include displayinterface(s) 1106 (e.g., a liquid crystal display (LCD), a touchscreen,a cathode ray tube (CRT), and software and hardware support for displaytechnologies), and audio interface(s) 1108 (e.g., microphones, speakersand software and hardware support for microphone input/output andspeaker input/output). The electronic device 1100 is also shown toinclude user interface(s) 1110 (e.g., keyboard, buttons, switches,touchpad, touchscreens, and software and hardware support for userinterfaces). The power management unit 1112 may utilize software and/orhardware logic to manage battery and discharge operations. Inembodiments, the power management unit 1112 may also manage powerdelivery to selected circuitry of the electronic device (e.g., thecommunication interfaces 1109) based on battery life.

The above description is intended to be illustrative, and notrestrictive. For example, the above-described embodiments (or one ormore aspects thereof) may be used in combination with each other. Otherembodiments will be apparent to those skilled in the art upon reviewingthe above description. In this document, the terms “a” or “an” are used,as is common in patent documents, to include one or more than one. Inthis document, the term “or” is used to refer to a nonexclusive or, suchthat “A or B” includes “A but not B,” “B but not A,” and “A and B,”unless otherwise indicated. In the event of inconsistent usages betweenthis document and those documents so incorporated by reference, theusage in the incorporated reference(s) should be consideredsupplementary to that of this document; for irreconcilableinconsistencies, the usage in this document supersedes the usage in anyincorporated references.

Although the claimed subject matter has been described with reference tospecific embodiments, it will be evident that various modifications andchanges may be made to these embodiments without departing from thebroader spirit and scope of what is claimed. Accordingly, thespecification and drawings are to be regarded in an illustrative ratherthan a restrictive sense. The scope of the claims should be determinedwith reference to the appended claims, along with the full scope ofequivalents to which such claims are entitled. In the appended claims,the terms “including” and “in which” are used as the plain-Englishequivalents of the respective terms “comprising” and “wherein.” Also, inthe following claims, the terms “including” and “comprising” areopen-ended; a system, device, article, or process that includes elementsin addition to those listed after such a term in a claim are stilldeemed to fall within the scope of that claim. Moreover, in thefollowing claims, the terms “first,” “second,” and “third,” etc. areused merely as labels and are not intended to impose numericalrequirements on their objects.

The Abstract of the Disclosure is provided to comply with 37 C.F.R. §1.72(b), requiring an abstract that will allow the reader to quicklyascertain the nature of the technical disclosure. It is submitted withthe understanding that it will not be used to interpret or limit thescope or meaning of the claims.

What is claimed is:
 1. A method comprising: receiving a frame from afirst wireless device, the frame comprising a first target wake time(TWT) element including a TWT request for TWT session and a firstbattery life value associated with the first wireless device; receivinga second battery life value associated with a second wireless device;responsive to the first TWT element, comparing the first battery lifevalue with the second battery life value; based on the comparison,responsive to the first battery life value being less than the secondbattery life value, adjusting a communication schedule by tearing downan existing TWT session associated with the second wireless device toallocate one or more timeslots of the existing TWT session to the firstwireless device; and transmitting a second TWT element to the firstwireless device, the second TWT element defining the TWT session.
 2. Themethod of claim 1, wherein the adjusting of the communication schedulefurther comprises: establishing the TWT session as a new TWT sessionassociated with the first wireless device; and allocating the one ormore timeslots to the TWT session.
 3. The method of claim 1, wherein theTWT session is associated with the second wireless device.
 4. The methodof claim 3, wherein the adjusting of the communication schedule based onthe comparison comprises, responsive to the first battery life valuebeing less than the second battery life value, scheduling the firstwireless device to communicate before the second wireless device duringthe TWT session.
 5. The method of claim 4, further comprisingtransmitting a third TWT element to the first wireless device, the thirdTWT element to trigger the first wireless device to communicate beforethe second wireless device during the TWT session.
 6. The method ofclaim 3, wherein the adjusting of the communication schedule based onthe comparison comprises, responsive to the first battery life valuebeing less than the second battery life value, disassociating the secondwireless device from the TWT session prior to associating the firstwireless device with the TWT session.
 7. The method of claim 1, whereinallocating the timeslots of the TWT session to the first wireless devicecomprises negotiating with the first wireless device to establish theTWT session, wherein a first wake interval for the TWT session is longerthan a second wake interval for the TWT session.
 8. A communicationdevice comprising: one or more processing devices; one or more memorydevices comprising instructions, wherein the one or more processingdevices to execute the instructions to: process a frame received from afirst wireless device, the frame comprising a first target wake time(TWT) element indicating a TWT request for TWT session and a firstbattery life value associated with the first wireless device; receive asecond battery life value associated with a second wireless device;compare the first battery life value with the second battery life value;and responsive to the first battery life value being less than thesecond battery life value, tear down an existing TWT session associatedwith the second wireless device to allocate one or more timeslots of theexisting TWT session to the first wireless device, associate the firstwireless device with a TWT session, and transfer to the first wirelessdevice a second TWT element defining the TWT session.
 9. Thecommunication device of claim 8, wherein the TWT session comprises a newTWT session, wherein the one or more processing devices to execute theinstructions to tear down the existing TWT session associated with thesecond wireless device and create the new TWT session.
 10. Thecommunication device of claim 8, wherein the TWT session is associatedwith the second wireless device.
 11. The communication device of claim10, wherein the one or more processing devices to execute theinstructions to disassociate the second wireless device from the TWTsession prior to the association of the first wireless device with theTWT session.
 12. The communication device of claim 10, whereinresponsive to the first battery life value being less that the secondbattery life value, the one or more processing devices to execute theinstructions to schedule the first wireless device to communicate beforethe second wireless device during the TWT session.
 13. A communicationdevice comprising: a transceiver; and one or more processing devicesconfigured to use the transceiver to: cause an access point (AP) to teardown an existing TWT session associated with a second communicationdevice to allocate one or more timeslots of the existing TWT session tothe communication device responsive to a first battery life valueassociated with the communication device being less than a secondbattery life value associated with the second communication device bytransmitting a frame comprising an outgoing target wake time (TWT)element indicating a TWT request for TWT session and the first batterylife value, wherein the AP is configured to receive the second batterylife value; receive, from the AP, an incoming target wake time (TWT)element that is based at least in part on the first battery life value,and communicate data with the AP during a TWT session of a TWT wakeinterval defined by the incoming TWT element, wherein the communicationdevice operates in a first mode during the communication of the data andoperates in a second mode after the communication of the data and duringthe TWT wake interval, wherein the operation in the second mode consumesless battery power than the operation in the first mode.
 14. Thecommunication device of claim 13, wherein the one or more processingdevices use the transceiver to transmit a frame including the firstbattery life value together with an outgoing TWT element to initiateassociation with the TWT session, wherein the incoming TWT element isresponsive to the outgoing TWT element.
 15. The communication device ofclaim 13, wherein the one or more processing devices compare the firstbattery life value to a minimum battery life threshold, wherein the oneor more processing devices use the transceiver to transmit the firstbattery life value responsive to the first battery life value being lessthan the minimum battery life threshold.
 16. The communication device ofclaim 13, wherein the one or more processing devices use the transceiverto communicate data with the AP during a first portion of the TWTsession, wherein the communication device operates in the second modeduring a second portion of the TWT session.
 17. A system comprising: oneor more antennas to transmit and receive radio frequency signals; anintegrated circuit (IC) coupled to the antenna, the IC comprising: atransceiver; and communication protocol logic to use the transceiver to:cause an access point (AP) to tear down an existing TWT sessionassociated with a second IC to allocate one or more timeslots of theexisting TWT session to the IC responsive to a first battery life valueassociated with the IC being less than a second battery life valueassociated with the second IC by transmitting a frame comprising anoutgoing target wake time (TWT) element including a TWT request for TWTsession and the first battery life value to the AP, wherein the AP isconfigured to receive the second battery life value, receive, from theAP, an incoming TWT element that is based at least in part on the firstbattery life value, and communicate data with the AP during a TWTsession of a TWT wake interval defined by the incoming TWT element,wherein the IC to operate in a first mode during the communication ofthe data and operate in a second mode after the communication of thedata and during the TWT wake interval, wherein the operation in thesecond mode consumes less battery power than the operation in the firstmode.
 18. The system of claim 17, further comprising a power statusmonitor to compare the first battery life value to a minimum batterylife threshold value, wherein the communication protocol logic to usethe transceiver to transmit the first battery life value responsive tothe first battery life value being less than the minimum battery lifethreshold value.
 19. The system of claim 17, wherein the communicationprotocol logic to use the transceiver to communicate data with the APduring a first portion of the TWT session, wherein the IC to operate inthe second mode during a second portion of the TWT session.